Hey, I have a great idea for a megastructure. The Great Spirit Robot from Lego Bionicle (2001-2010). It stands 40 million feet tall, or about 95% of Earth's diameter. It might also make a good spaceship. And maybe you could also make Aqua Magna, Bota Magna, and Bara Magna (which make up Spherus Magna, orbiting the sun Solis Magna).

Not the nebula, but the model file 'schleier.cfg'. If I use this file, I have the Superman nebula as background.

This is of course because I have no idea what I'm doing when I create such a nebula.

Actually I should be a nebula, which is shaped like a cup or a bowl, in which my cluster is hidden.And it should be two nebula: outside a dark nebula which makes everything invisible, what is inside, and inside a colored nebula, like in some of my screenshots.

But dark nebula do not hide anything in SpaceEngine. And I'm not an expert with nebula.